Pinch type bending roll method and means



Dec. 4, 1945- J. c. ROSE arm. 0,

PINCH TYPE BENDING ROLL METHOb AND MEANS Filed July 25, 1942 2Sheets-Sheet 1 JESS c. ROSE 'INVENTOR GEORGE 5. smmrsy 7 T NE}! Dec. 4,1945. J. c. ROSE ETAL 2,390,274

PINCH TYPE BENDING ROLL METHOD AND MEANS Fild July 25, 1942 2Sheets-Sheet 2 J a S INVENTOR GEORGE STANKEY Patented Dec. 4, 1945 Jess0. Rose and Calm, assignors to Angelcs, Calif...

George E. Stankey, Los Angeles,

Bardwell & a. corporation of California McAlister, Los

Application July 275, 2, Serial. No. 2.306

Claims.

hi n e n re a es enerall to the art of .nd g n arly e tend d stock ofvarious cr ssectional shapes to predetermined curvatures by m ans fpinch-type bending ro ls, and he g neral object of the invention is theprovision of improved methods and means for supp rting the stock as itis run through the bending oll.

In bending stock by means of pinch type bend, ing rolls, the stock ispassed between two rolls which'closely support or pinch? the metalbetween them as it is bent. A. leading r011 supports the stock justahead of the two pinch rolls, and a. forming.rol1 engages and deflectsit just beyond them, causing the metal to bend at the pinch rolls. Theaim in operating such bending rolls is to confine e metal ely at t epinc rolls, i. e., at the point of bend, so as to control the, flow ofthe metal (which must be stretched at one edge and packed or shrunk atthe other) in such a way as to avoid wrink ing. buck1ing,twisting orother distortions. Pinchty e bending rolls v be n ery successiully us dn the past to bend certain angle and other sections when the metal is ofsome substantial thickness. However, with relatively thin stock, say of3%? thickness or ess, reat. difli u ty is ncountered. As a matter fa ithas here o ore been absolutely impossible to end l ht ua e angle andother sections, made up for instance of stainless steel, without w n l nor buck t e meta The primary object of the present invention istherefore the provision of a method and means for bending relativelylight guage stock of various cross-sectional shapes by me ns ofconventional pinch typebending rolls. .In accordance with the invention,the relatively light guage stock to b r n thr u h the bend n Fi 2 is aside e evat on of the s biect mat e sh w in F g.1;

pa b ok n a ay, a r of spring P d ith a. -se tion st i packedtherebetween;

Fig. 3 is a transverse section taken on lin 3-4 of ig. 2; i

Fig. 4 is a transverse section taken on line 4-4 of Fig. 2; a

Fig. 4a is a modification;

Fig. 5 is a transverse section taken on line 5-.-5 of Fig. 2 i V Fig. 6is a schematic side elevation of a pinchtype bending roll adapted tocarry out the present invention;

Fig. 7 i a section view similar to Fig, 4, but showing a on line l--'!of Fig. 6:

ig. 8. is a section on lin 8?8 of Fig. 6;

Fig. 9 is a section on line 9.9 of Fig. 6;

Fig. 10 is a view similar to a portion of Fig, 1, but showing amodification;

Fig. 11 is a transverse section on line i [*H of Fig. 10;

Fig. 12 is a view similar to Fig. 6, but showing additionally the use ofa side thrust roller designed to impart a curvature to the stock in adirection at right angles to the direction of bend normally imparted bythe bending roll; and c Fig, 13 is a view taken as indicated by linel3-l3inFig. 12. i

Figs. 6 to 9, inclusive, show schematically a fore or less conventionalpinch-type bending roll, such as may be utilized in practicing thepresent invention; for a. more complete disclosure of such a bendingroll, see our Patent .No. 2,335,028- entitled fPinch type bending rollissued November 23, 1943. This bending roll comprises two pinch rollshafts 20 and 2|, either one of which, or both, may be driven throughany suitable driving arrangements. Shaft 20 carries a series of threerolls 22, 23, and 24, of which rolls 22 and 24 are of the same diameter,and roll 23 is of a lesser diameter as typically shown in Fig.7. Shaft2| carries a singl roll 25., a marginal portion of which is received inthe space between the rails 22 and 24.

The peripheries of the opposed rolls 23 and 25 together with portions ofthe side faces of rolls 22 and 24 define a rectangular opening orpassageway for the stock Ahead of the pinch roll shaft is aleading roll26, which idles on, a suitable spindle 21. nd which c m rises hre d ks6a, 2 12 and 260 definin a groove 28 adapted to receive and confinelaterto be bent and the-flexible supporting elements, as presently to bedescribed.

v to impart to fine laterally the stock and supporting elementstherefor, this roll 33 being mounted on a shaft 32, which may be driven,through any suitable arrangements not necessary here to illustrate, soas disk 30b defining the bottom of groove 3| rotation at the sameperipheral speed as pinch roll 25, the rolls 30 and of course turning inthe same direction.

Assuming the member S to be formed to be, for instance. of Z-section(see Fig. 4), the procedure is as follows: The member S is packedbetween two sets or pads 40 of long, flat spring elements or leaves 4|,the web 42 of the Z-section member being abutted by the longitudinaledges of the spring leaves of each pad, and eachpad being of a thicknesssubstantially equal to the height of the web of the Z-section memberplus the thickness of one of its flanges. These leaves 4! are preferablyslightly greater in width than the widths of the flanges 43 of theZ-section member, and they are preferably formed of spring steel, of athickness of the order, typically, of .031", though this is subject tomodification; In Figs. 1 and 2, a substantial portion of the lengths ofthe spring pads and Z-section member have been broken out. It is to beunderstood that these members may be of any length; for instance for aZ-section member of a length of 6, the spring pads may be '7 in length.They should in any case be at least approximately one foot longer thanthe stock to be bent.

Leaves 4| of each spring pad 40 are preferably integrated at the noseends of the pads; forinstance, as indicated at 44in F g. 2, the leavesmay be brazed each to inch or an inch and a half at the nose ends of thepads. The brazing material is not only applied along the edges of thespring leaves, but sweated in between them so that, in effect, thespring pad is made solid at its nose end. The two pads 40, with theZ-section member S packed therebetween. are preferably provided with anencircling band 46, which secures the pack in assembly and which isslidably mounted on the pads, so that a rearward direction, and finallypulled off the rearward ends of the pads as the pads go into the bendingroll.

Thelongitudinal edges of spring pads4ll support the web 42 of member Sduring the bending operation. but leave the flanges 43 unprotected andsubject to wrinkling. To support these flanges 43, long, flat springmembers or leaves 41, formed of spring steel. and of widthsapproximately double the widths of the spring leaves 4!, are placed atthe top and bottom sides of the pack. in such manner that one-half ofeach such member 41 lies flat against the otherwise exposed face of oneof the flanges 43. The other halves of the members 41 engage the op osedspring pad 40, as clearly shown in Fig. 4. These members 41 are made asthick as possible consistent with bending through the curved path whichthey must follow. and may be of thicknesses ranging typically between/8" and A1", though this is of course not to be taken as limitativee Thepack P as thus assembled is then run through the bending roll as a unit,the encircling band 46 being moved in a rearward direction on the padsas the pack goesinto the bending roll,

being finally removed'from the rearward ends of the pads. I

r The pads 40 will be understood to be of such widths that, takentogether with the thickness of the web 42 of the member S to be bent,the total the next for a distance of an it can be manually moved incation of the set-up for a member S' thickness dimension of the pack issuch as will just be received, with comparatively close-sliding fit,between the rolls 22 and 24 of the bending roll (see Fig. '7), andadjustments are so made that the vertical thickness of the pack,measured between the outside faces of the two outside spring leaves 41,is such as will just permit the pack to be received between the rolls 23and 25, the latter pinching the pack between them with a pressure suchas is usual in the operation of pinch-type bending rolls. It will beunderstood that in conventional pinch-type bending rolls, the two shafts20 and 2| carrying the rolls 23 and 25 are vertically adjustablerelatively to one another, and this adjustment is so made as to applythe proper pressure to the pack. The longitudinal edges of the springleaves 4| making up the two spring pads 40, as thus confined between thelateral faces of the two rolls 22 and 24, support the full width of theweb 42 of the member S which is to be bent, and the two flat springmembers41, in cooperation with'the pads, confine and support the flanges43. The spring pad 40, as well as the spring members 41, conform readilyto the curved path for which the bending roll is adjusted, and themember S is bent to the desired shape, and because of the supportprovided, assumes such shape without wrinkling, buckling, twistng orbecoming otherwise deformed. The close support provided for the member Son all its surfaces thus permits it to be shrunk" and stretched indifferent portions without introduction of the various distortions whichhave heretofore been inevitable with relatively light guage material.

The invention is of course not restricted-in application t0 theparticular Z-sectio-n stock chosen for illustrative purposes. Fig. ie,for instance, which is a view similar to Fig. 4, showsa modifiof anglesection. In this instance, the set-up is the same as before, with theexceptionthat, the member S havingbut. one flange 48, but one of theflat spring members 41 is needed Otherwise, the spring pads may be 49 ofthe angle member S'- being in this instance confined between the springpads 4| thesame as the web 42 of the Z-section member S described first.

Figs. 10, 11, 12 and 13 show a modification of the invention which isemployed when the stock is to be bent in two directions, one at rightangles to the other. In such a case, the bending roll is equipped withan additional rollilL-whichis of a width substantially equal to thethickness of a spring pad, and which engages the lateral edge of theadjacent spring pad just beyond forming roll 3!]. In this instance, eachpad, here designated by numeral a, and which, excepting for departuresnoted, will be understood to be the same as the pad 40, s so formed asto be flexible in two directions. Toaccomplish this, the'pad may be madeup of a plurality of rods or bars Ma, flexible in both directions, andpreferably of square or rectangular cross-section, as illustrated inFig. 11. The stock S has again been illustrated as a member ofZ-section, though this is of course not limitative, and the stock mightequally as well be of angle or other section. The stock S being ofZ-section, however, the two flanges 43 thereof are again supportedbylong, fiat spring members or leaves 41, like the spring members 41 ofFigs. 2 to 5. It will be understood that the lateral thrust roller ofthe bending roll will engage the adjacent pad 4041 between the the sameas before, the web members 41, which are not laterally'flexible, andfunction to deflect the pads "a and the stock in a lateral direction, soas to impart to the "latter the desired lateral curvature.

The above description of typical procedures and instrumentalities forcarrying the instant invention into effect will serve to impart acomplete knowledge of the principles underlying the invention, and willenable the invention to be applied to stock of various cross-sectionalforms not here specifically illustrated. Also, as will be evident, theparticular illustrative procedures and instrumentalities are susceptibleto considerable variation and modification without departing from thespirit and scope of the invention or of the appended claims.

We claim:

1. The method of bending relatively thin linearly extended sheet metalstock whose cross section includes a longitudinal web that is parallelto the plane of the bend, and a flange joined to an edge of said web anddisposed at right angles thereto, by means of a pinch type bending roll,that includes packing a pair of linearly extended spring pads againstopposite surfaces of said web, and with the pad on one side of the webabutting said flange, said spring pads being flexible in the directionthe stock is to be bent, applyin a flat spring leaf against the exposedface of said flange, so as to pack said flange between the oneispringpad and said spring leaf, and passing the stock together with said pairof spring pads and leaf spring through the bending roll.

2. The method of bending relatively thin linearly extended sheet metalstock whose cross section includes a longitudinal web that is parallelto the plane of the bend, and a flange joined to an edge of said web anddisposed at right angles thereto, by means of a pinch type bending roll,that includes packing a pair of linearly extended spring pads againstopposite surfaces of said web, and with the pad on one side of the webabutting ,said flange, said spring pads each comprising a plurality ofparallel spring elements which are flexible in the direction the stockis to be bent, applying a flat spring leaf against th exposed face ofsaid flange, so as to pack said flange between the one spring pad andsaid spring leaf, and passing the stock together with said pair ofspring pads and leaf springthrough the bending roll.

3. The method of bending relatively thin linearly extended sheet metalstock whose cross section includes a longitudinal web that is parallelto the plane of the bend, and a flange joined to an edge of said web anddisposed at right angles thereto, by means of a pinchtype bending roll,that includes packing a pair of linearly extended spring pads againstopposite surfaces of said Web, and with the pad on one side of the webabutting said flange, said spring pads each comprising a stack ofparallel flat spring leaves whose longitudinal side edges engage theweb, applying a flat spring leaf against the exposed face of saidflange, so as to pack said flange between the one spring pad and saidspring leaf, and passing the stock together with said pad or spring padsand leaf spring through the bending roll.

4. The method of bending relatively-thin linearly extended sheet metalstock whose cross section includes a longitudinal web that is parallelto the plane of th bend, and flanges joined to opposite edges of saidweb and disposed at right angles thereto, by means of a pinch typebending roll, that includes packing a pair of linearly extended springads against a posite surfaces of said web, and with each flangesupported by an abutting spring pad, said spring pads being flexible inthe direction the stock is to be. bent, applying flat spring leavesagainst the exposed faces of said flanges, so as to pack each saidflange between a spring pad and a spring leaf, and passing the stocktogether with said pair of spring pads and said spring leaves throughthe bending roll. 7

5; The method of bending relatively thin line! arlyextended sheet metalstock whose cross Section includes a longitudinal web that is parallelto the plane of the bend, and flanges joined to opposite edges of saidweb and disposed at right angles thereto, by means of a, pinch typebending roll, that includes packing a pair of linearly extended springpads against opposite surfaces of said web, and with each flangesupported by an abutting spring pad, said spring pads each comprising aplurality of parallel spring elements which are flexible in thedirection the stock is to be bent, applying flat spring leaves againstthe exposed faces of said flanges, so as to pack each said flangebetween a spring pad and a spring leaf, and passing the stock togetherwith said pair of spring pads and said spring leaves through the bendingroll.

6. The method of bending relatively thin linearly extended sheet metalstock whose cross section includes a longitudinal web that is parallelto the plane of the bend, and flanges joined to opposite edges of saidweb and disposed at right angles thereto, by means of a pinch typebending.

roll, that includes packing a pair of linearly extended spring padsagainst opposite surfaces of said web, and with each flange supported byan abutting spring pad, said spring pads each comprising a plurality ofparallel spring elements which are flexible in the direction the stockis to be bent, applying flat spring leaves against the exposed faces ofsaid flanges, so as to pack each said flange between a spring pad and aspring leaf, and passing the stock together with said pair of springpads and said spring leaves through the bending roll.

'7. The method of bending relatively thin linearly extended sheet metalstock whose cross sec-v tion includes a longitudinal web that isparallel to the plane of the bend, and flanges joined to and turnedoppositely from opposite edges of said web, by means of a pinch typebending roll, that includes packing a pair of linearly extended springpads against opposite surfaces of said web, and with each flangesupported by one of said spring pads, said spring pads being flexible inthe direction the stock is to be bent, applying flat spring leavesagainst the exposed faces of said flanges, so as to pack each saidflange between a spring pad and a spring leaf. and passing the stocktogether with said pair of spring pads and said s ring leaves throughthe bending roll.

8. ,The method of bending a relatively thin linearl extended member ofuniform cross-section in a pinch type bending roll, said member havingsurfaces likely to become deformed during the bending operation, thatincludes setting up the pinch rolls of the bending roll to define apassageway for the member of rectangular crosssection and of greatercross-sectional area than the member, packing the member between aplurality of flexible longitudinally extending elements closely engagingand supporting said surfaces, forming said elements and member into apack of cross-sectional size conforming to said passageway defined bysaid pinch rolls, and pass- 7 ing the pack longitudinally through saidpassageway.

9. A spring pad flexible in two directions at right angles to oneanother comprising a bundle of parallel linearly extended springelements flexible in two directions arranged in a plurality ofcontacting vertical and horizontal rows and integrated to one another atone end.

10. Means for packing a relatively thin linearly extended sheet metalmember whose cross section includes a longitudinal web parallel to theplane of the bend, and a flange joined to an edge of said Web anddisposed at right angles thereto,

duringbending thereof in a pinch type bending roll, comprising: a pairof linearly extended spring pads consisting of a stack of relativelythin spring leaves adapted to be positioned adjacent oppositesurfaces ofsaid web, and with the pad on one side of the web in engagement with theinside surface of said flange, and a spring leaf relatively thicker thanthe aforementioned spring leaves adapted to be applied to the outsidesurface of said flange.

JESS C. ROSE.

GEORGE E. STANKEY.

